Bostitch BTE820 User manual

Instruction manual
Manuel d’instructions
Manual de’instrucciones
INSTRUCTIVO DE OPERACIÓN, CENTROS DE SERVICIO Y PÓLIZA DE GARANTÍA.
ADVERTENCIA: LÉASE ESTE INSTRUCTIVO ANTES DE USAR EL PRODUCTO.
BTE820
www.BOSTITCH.com
7A
4-1/2 inch (114mm) angle grinder/cut off tool
Meuleuse d’angle/outil coupant de 114 mm (4 1/2 po) et de 7 A
Esmeriladora angular/cortar herramienta de 7 mperios y 114 mm (4-1/2 pulg.)

2
General Power Tool Safety Warnings
WARNING: Read all safety warnings and all instructions. Failure to follow the
warnings and instructions may result in electric shock, fire and/or serious injury.
SAVE ALL WARNINGS AND INSTRUCTIONS FOR FUTURE REFERENCE
The term “power tool” in the WARNINGs refers to your mains-operated (corded) power
tool or battery-operated (cordless) power tool.
SAVE THESE INSTRUCTIONS
1) WORK AREA SAFETY
a) Keep work area clean and well lit. Cluttered or dark areas invite accidents.
b) Do not operate power tools in explosive atmospheres, such as in the presence of flammable
liquids, gases or dust. Power tools create sparks which may ignite the dust or fumes.
c) Keep children and bystanders away while operating a power tool. Distractions can cause
you to lose control.
2) ELECTRICAL SAFETY
a) Power tool plugs must match the outlet. Never modify the plug in any way. Do not use
any adapter plugs with earthed (grounded) power tools. Unmodified plugs and matching
outlets will reduce risk of electric shock.
b) Avoid body contact with earthed or grounded surfaces such as pipes, radiators, ranges and
refrigerators. There is an increased risk of electric shock if your body is earthed or grounded.
c) Do not expose power tools to rain or wet conditions. Water entering a power tool will
increase the risk of electric shock.
d) Do not abuse the cord. Never use the cord for carrying, pulling or unplugging the
power tool. Keep cord away from heat, oil, sharp edges or moving parts. Damaged or
entangled cords increase the risk of electric shock.
e) W hen operating a power tool outdoors, use an extension cord suitable for outdoor
use. Use of a cord suitable for outdoor use reduces the risk of electric shock.
f) If operating a power tool in a damp location is unavoidable, use a ground fault circuit
interrupter (GFCI) protected supply. Use of a GFCI reduces the risk of electric shock.
3) PERSONAL SAFETY
a) Stay alert, watch what you are doing and use common sense when operating a power
tool. Do not use a power tool while you are tired or under the influence of drugs,
alcohol or medication. A moment of inattention while operating power tools may result in
serious personal injury.
b) Use personal protective equipment. Always wear eye protection. Protective equipment
such as dust mask, nonskid safety shoes, hard hat, or hearing protection used for appropriate
conditions will reduce personal injuries.
c) Prevent unintentional starting. Ensure the switch is in the off position before
connecting to power source and/ or battery pack, picking up or carrying the tool.
Carrying power tools with your finger on the switch or energizing power tools that have the
switch on invites accidents.
d) Remove any adjusting key or wrench before turning the power tool on. A wrench or a
key left attached to a rotating part of the power tool may result in personal injury.
e) Do not overreach. Keep proper footing and balance at all times. This enables better
control of the power tool in unexpected situations.
SAFETY GUIDELINES - DEFINITIONS
It is important for you to read and understand this manual. The information it contains
relates to protecting YOUR SAFETY and PREVENTING PROBLEMS. The symbols
below are used to help you recognize this information.
DANGER: Indicates an imminently hazardous situation which, if not avoided,
will result in death or serious injury.
WARNING: Indicates a potentially hazardous situation which, if not avoided,
could result in death or serious injury.
CAUTION: Indicates a potentially hazardous situation which, if not avoided,
may result in minor or moderate injury.
NOTICE: Used without the safety alert symbol indicates potentially hazardous
situation which, if not avoided, may result in property damage.

3
f) Dress properly. Do not wear loose clothing or jewelry. Keep your hair, clothing and gloves
away from moving parts. Loose clothes, jewelry or long hair can be caught in moving parts.
g) If devices are provided for the connection of dust extraction and collection
facilities, ensure these are connected and properly used. Use of dust collection can
reduce dust-related hazards.
4) POWER TOOL USE AND CARE
a) Do not force the power tool. Use the correct power tool for your application. The correct
power tool will do the job better and safer at the rate for which it was designed.
b) Do not use the power tool if the switch does not turn it on and off. Any power tool that
cannot be controlled with the switch is dangerous and must be repaired.
c) Disconnect the plug from the power source and/or the battery pack from the power tool
before making any adjustments, changing accessories, or storing power tools. Such
preventive safety measures reduce the risk of starting the power tool accidentally.
d) Store idle power tools out of the reach of children and do not allow persons unfamiliar
with the power tool or these instructions to operate the power tool. Power tools are
dangerous in the hands of untrained users.
e) Maintain power tools. Check for misalignment or binding of moving parts, breakage of
parts and any other condition that may affect the power tool’s operation. If damaged,
have the power tool repaired before use. Many accidents are caused by poorly maintained
power tools.
f) Keep cutting tools sharp and clean. Properly maintained cutting tools with sharp cutting
edges are less likely to bind and are easier to control.
g )Use the power tool, accessories and tool bits, etc. in accordance with these instructions,
taking into account the working conditions and the work to be performed. Use of the
power tool for operations different from those intended could result in a hazardous situation.
5) SERVICE
a) Have your power tool serviced by a qualified repair person using only identical
replacement parts. This will ensure that the safety of the power tool is maintained.
SAFETY INSTRUCTIONS FOR ALL OPERATIONS
SAFETY WARNINGS COMMON FOR GRINDING, SANDING,
WIRE BRUSHING OR ABRASIVE CUTTING-OFF OPERATIONS
a) This power tool is intended to function as a grinder, wire brush, sander or cut-
off tool. Read all safety warning instructions, illustrations and specifications
provided with this power tool. Failure to follow all instructions listed below may
result in electric shock, fire and/or serious injury. Operations such as polishing are
not recommended to be performed with this power tool. Operations for which the
power tool was not designed may create a hazard and cause personal injury.
b) Do not use accessories which are not specifically designed and
recommended by the tool manufacturer. Just because the accessory can be
attached to your power tool, it does not assure safe operation.
c) The rated speed of the accessory must be at least equal to the maximum
speed marked on the power tool. Accessories running faster than their rated
speed can break and fly apart.
d) The outside diameter and the thickness of your accessory must be within
the capacity rating of your power tool. Incorrectly sized accessories cannot be
adequately guarded or controlled.
e) The arbor size of wheels, flanges, backing pads or any other accessory must
properly fit the spindle of the power tool. Accessories with arbor holes that do
not match the mounting hardware of the power tool will run out of balance, vibrate
excessively and may cause loss of control.
f) Do not use a damaged accessory. Before each use inspect the accessory such
as abrasive wheel for chips and cracks, backing pad for cracks, tear or excess
wear, wire brush for loose or cracked wires. If power tool or accessory is dropped,
inspect for damage or install an undamaged accessory. After inspecting and
installing an accessory, position yourself and bystanders away from the plane of
the rotating accessory and run the power tool at maximum no-load speed for one
minute. Damaged accessories will normally break apart during this test time.
g) Wear personal protective equipment. Depending on application, use face
shield, safety goggles or safety glasses. As appropriate, wear dust mask,
hearing protectors, gloves and work shop apron capable of stopping small
abrasive or workpiece fragments. The eye protection must be capable of

4
stopping flying debris generated by various operations. The dust mask or
respirator must be capable of filtrating particles generated by your operation.
Prolonged exposure to high intensity noise may cause hearing loss.
h)
Keep bystanders a safe distance away from work area. Anyone entering the work
area must wear personal protective equipment. Fragments of workpiece or of a
broken accessory may fly away and cause injury beyond immediate area of operation.
i) Hold power tool by insulated gripping surfaces only, when performing an
operation where the cutting accessory may contact hidden wiring or its own
cord. Cutting accessory contacting a “live” wire may make exposed metal parts of
the power tool “live” and shock the operator.
j) Position the cord clear of the spinning accessory. If you lose control, the cord may be
cut or snagged and your hand or arm may be pulled into the spinning accessory.
k) Never lay the power tool down until the accessory has come to a complete stop.
The spinning accessory may grab the surface and pull the power tool out of your control.
l) Do not run the power tool while carrying it at your side. Accidental contact with
the spinning accessory could snag your clothing, pulling the accessory into your body.
m) Regularly clean the power tool’s air vents. The motor’s fan will draw the dust inside
the housing and excessive accumulation of powdered metal may cause electrical hazards.
n) Do not operate the power tool near flammable materials. Sparks could ignite
these materials.
o) Do not use accessories that require liquid coolants. Using water or other liquid
coolants may result in electrocution or shock.
p) Do not use Type 11 (flaring cup) wheels on this tool. Using inappropriate
accessories can result in injury.
q) Always use auxiliary handle. Tighten the handle securely. The auxiliary
handle should always be used to maintain control of the tool at all times.
r) Use clamps or another practical way to secure and support the work piece
to a stable platform. Holding the work by hand or against your body leaves it
unstable and may lead to loss of control.
s) When starting the tool with a new or replacement wheel, or a new or
replacement wire brush installed, hold the tool in a well protected area and let
it run for one minute. If the wheel has an undetected crack or flaw, it should burst
in less than one minute. If the wire brush has loose wires, they will be detected.
Never start the tool with a person in line with the wheel. This includes the operator.
FURTHER SAFETY INSTRUCTIONS FOR ALL OPERATIONS
KICKBACK AND RELATED WARNINGS
Kickback is a sudden reaction to a pinched or snagged rotating wheel, backing pad, brush
or any other accessory. Pinching or snagging causes rapid stalling of the rotating accessory
which in turn causes the uncontrolled power tool to be forced in the direction opposite of the
accessory’s rotation at the point of the binding. For example, if an abrasive wheel is snagged
or pinched by the workpiece, the edge of the wheel that is entering into the pinch point can
dig into the surface of the material causing the wheel to climb out or kick out. The wheel
may either jump toward or away from the operator, depending on direction of the wheel’s
movement at the point of pinching. Abrasive wheels may also break under these conditions.
Kickback is the result of tool misuse and/or incorrect operating procedures or
conditions and can be avoided by taking proper precautions as given below:
a) Maintain a firm grip on the power tool and position your body and arm to allow
you to resist kickback forces. Always use auxiliary handle, if provided, for
maximum control over kickback or torque reaction during start up. The operator
can control torque reaction or kickback forces, if proper precautions are taken.
b) Never place your hand near the rotating accessory. Accessory may kickback
over your hand.
c) Do not position your body in the area where power tool will move if
kickback occurs. Kickback will propel the tool in direction opposite to the wheel’s
movement at the point of snagging.
d) Use special care when working corners, sharp edges etc. Avoid bouncing
and snagging the accessory. Corners, sharp edges or bouncing have a
tendency to snag the rotating accessory and cause loss of control or kickback.
e) Do not attach a saw chain woodcarving blade or toothed saw blade. Such
blades create frequent kickback and loss of control.

5
SAFETY WARNINGS SPECIFIC FOR GRINDING AND
ABRASIVE CUTTING-OFF OPERATIONS
a) Use only wheel types that are recommended for your power tool and the
specific guard designed for the selected wheel. Wheels for which the power
tool was not designed cannot be adequately guarded and are unsafe.
b) The guard must be securely attached to the power tool and positioned for
maximum safety, so the least amount of wheel is exposed towards the
operator. The guard helps to protect operator from broken wheel fragments and
accidental contact with wheel.
c) Wheels must be used only for recommended applications. For example: do
not grind with the side of cut-off wheel. Abrasive cut-off wheels are intended for
peripheral grinding, side forces applied to these wheels may cause them to shatter.
d) Always use undamaged wheel flanges that are of correct size and shape for your
selected wheel. Proper wheel flanges support the wheel thus reducing the possibility of
wheel breakage. Flanges for cut-off wheels may be different from grinding wheel flanges.
e) Do not use worn down wheels from larger power tools. Wheel intended for
larger power tool is not suitable for the higher speed of a smaller tool and may burst.
ADDITIO NAL SAFETY WARNINGS SPECIFIC FOR ABRASIVE
CUTTING-OFF OPERATION
a) Do not “jam” the cut-off wheel or apply excessive pressure. Do not attempt
to make an excessive depth of cut. Over stressing the wheel increases the
loading and susceptibility to twisting or binding of the wheel in the cut and the
possibility of kickback or wheel breakage.
b) Do not position your body in line with and behind the rotating wheel. When
the wheel, at the point of operation, is moving away from your body, the possible
kickback may propel the spinning wheel and the power tool directly at you.
c) When wheel is binding or when interrupting a cut for any reason, switch off
the power tool and hold the power tool motionless until the wheel comes
to a complete stop. Never attempt to remove the cut-off wheel from the cut
while the wheel is in motion otherwise kickback may occur. Investigate and
take corrective action to eliminate the cause of wheel binding.
d) Do not restart the cutting operation in the workpiece. Let the wheel reach
full speed and carefully reenter the cut. The wheel may bind, walk up or
kickback if the power tool is restarted in the workpiece.
e) Support panels or any oversized workpiece to minimize the risk of wheel
pinching and kickback. Large workpieces tend to sag under their own weight.
Supports must be placed under the workpiece near the line of cut and near the
edge of the workpiece on both sides of the wheel.
f) Use extra caution when making a “pocket cut” into existing walls or other
blind areas. The protruding wheel may cut gas or water pipes, electrical wiring or
objects that can cause kickback.
SAFETY WARNINGS SPECIFIC FOR SANDING OPERATIONS
a) Do not use excessively oversized sanding disc paper. Follow manufacturers
recommendations, when selecting sanding paper. Larger sanding paper
extending beyond the sanding pad presents a laceration hazard and may cause
snagging, tearing of the disc or kickback.
SAFETY WARNINGS SPECIFIC FOR WIRE BRUSHING OPERATIONS
a) Be aware that wire bristles are thrown by the brush even during ordinary
operation. Do not overstress the wires by applying excessive load to the
brush. The wire bristles can easily penetrate light clothing and/or skin.
b) If the use of a guard is recommended for wire brushing, do not allow any
interference of the wire wheel or brush with the guard. Wire wheel or brush
may expand in diameter due to work and centrifugal forces.
c) Safety Glasses: Safety Goggles or safety glasses with side shields and a full face
shield compliant with ANSI Z87.1 must be worn by the operator and others that
are within 50 feet of the use of this product.
ADDITIONAL SAFETY INFORMATION
• DonotuseType1flatabrasiveordiamondwheelswithoutproperType1guard.
WARNING: ALWAYS use safety glasses. Everyday eyeglasses are NOT safety glasses. Also

6
use face or dust mask if operation is dusty. ALWAYS WEAR CERTIFIED SAFETY EQUIPMENT:
  •ANSIZ87.1eyeprotection(CAN/CSAZ94.3),
  •ANSIS12.6(S3.19)hearingprotection,
  •NIOSH/OSHA/MSHArespiratoryprotection.
WARNING: Some dust created by power sanding, sawing, grinding, drilling,
and other construction activities contains chemicals known to the State of
California to cause cancer, birth defects or other reproductive harm. Some
examples of these chemicals are:
  •leadfromlead-basedpaints,
  •crystallinesilicafrombricksandcementandothermasonryproducts,and
  •arsenicandchromiumfromchemically-treatedlumber.
Your risk from these exposures varies, depending on how often you do this type of work.
To reduce your exposure to these chemicals: work in a well ventilated area, and work
with approved safety equipment, such as those dust masks that are specially designed
to filter out microscopic particles.
• Avoid prolonged contact with dust from power sanding, sawing, grinding, drilling,
and other construction activities. Wear protective clothing and wash exposed
areas with soap and water. Allowing dust to get into your mouth, eyes, or lay on the
skin may promote absorption of harmful chemicals.
WARNING: Use of this tool can generate and/or disperse dust, which may cause
serious and permanent respiratory or other injury. Always use NIOSH/OSHA approved
respiratory protection appropriate for the dust exposure. Direct particles away from face and body.
WARNING: Always wear proper personal hearing protection that conforms
to ANSI S12.6 (S3.19) during use. Under some conditions and duration of use, noise
from this product may contribute to hearing loss.
WARNING: Always use eye protection. All users and bystanders must wear
eye protection that conforms to ANSI Z87.1.
WARNING: When not in use, place grinder on a stable surface where it will
not move inadvertently, roll or cause a tripping or falling hazard.
CAUTION: To reduce the risk of personal injury, use extra care when working
into a corner or edge because a sudden, sharp movement of the tool may be experienced
when the wheel or other accessory contacts a secondary surface or a surface edge.
SYMBOLS
• Thelabelonyourtoolmayincludethefollowingsymbols.Thesymbolsandtheir
definitions are as follows:
V..................volts A...................amperes
Hz................hertz W..................watts
min ..............minutes ................alternating current
............direct current no.................rated speed
................Class I Construction ...............earthing terminal
(grounded) .................safety alert symbol
................Class II Construction .../minorrpm....revolutions or reciprocation
(double insulated) per minute
............Read instruction manual before use
................Use proper eye protection
................Use proper hearing protection
................Use proper respiratory protection
• Whenusinganextensioncord,besuretouseoneheavyenoughtocarrythe
current your product will draw. An undersized cord will cause a drop in line voltage
resulting in loss of power and overheating. The following table shows the correct
size to use depending
on cord length and
nameplate ampere
rating. If in doubt, use
the next heavier gauge.
The smaller the gauge
number, the heavier the
cord.
MINIMUM GAUGE FOR CORD SETS
Volts Total Length of Cord in Feet
120V 0-25 26-50 51-100 101-150
  (0-7,6m)(7,6-15,2m)(15,2-30,4m)(30,4-45,7m)
Ampere Rating
More Notmore AmericanWireGauge
Than Than
6 - 10 18 16 14 12

7
Assembly
WARNING: To prevent accidental operation, turn off and unplug tool before
performing the following operations. Failure to do this could result in serious personal injury.
AUXILIARY HANDLE
WARNING:ThishandleSHOULDBEUSEDATALLTIMEStomaintaincomplete
control of the tool.
Anauxiliary3positionhandleisfurnishedwithyourgrinder.Itcanbescrewedinto
either side or the top of the gear case housing.
Accessories
It is important to choose the correct guards, backing pads and flanges to use with
grinderaccessories.Seepage9forinformationonchoosingthecorrectaccessories.
CAUTION: Accessories must be rated for at least the speed recommended on the
tool WARNING label. Wheels and other accessories running over their rated
accessory speed may fly apart and cause injury. Threaded accessories must have a 5/8
inch-11hub.Everyunthreadedaccessorymusthavea7/8inch(22mm)arborhole.Ifit
does not, it may have been designed for a circular saw. Use only the accessories shown
onpage9ofthismanual.Accessoryratingsmustalwaysbeabovetoolspeedasshown
on tool nameplate.
MOUNTING GUARD (FIGURES B & C)
CAUTION: Guards must be used with all grinding wheels, sanding flap discs,
wire brushes cut-off wheels and wire wheels. The tool may be used without a guard
onlywhensandingwithconventionalsandingdiscs.TheBTE820isprovidedwithaguard
intendedforusewithdepressedcenterwheels(Type27)andhubbedgrindingwheels
(Type27).Thesameguardisdesignedforusewithsandingflapdiscs(Type27and29)
andwirecupbrushes.GrindingandcuttingwithwheelsotherthanType27and29require
different accessory guards. A Type 1 guard is provided for use with a Type 1 wheel.
Both Type 27 and Type 1 guards attach and are removed in the same way as
described below.
1. Figure B-Opentheguardlatch(7),andalignthe
lugsontheguard(8)withtheslotsonthegear
casecover(9).
 2.Pushtheguarddownuntiltheguardlugsengage
and rotate freely in the groove on the gear case
hub.
 3.Withtheguardlatchopen,rotatetheguardintothe
desired working position. The guard body should be
positioned between the spindle and the operator to
provide maximum operator protection.
1
4
5
3
2
6
A
FUNCTIONAL DESCRIPTION
1. Paddle switch
1a. Lock off lever
2. Cord
3. Toolfreeguard
4. Bodygrip
5. Auxiliaryhandle(3positions)
6. Spindlelockbutton
7.Guard(Type27orType1if
soequipped)(notshown)
1a
B
9
8
7

8
 4.Figure C-Closetheguardlatch(7)tosecurethe
guard on the gear case. You should not be able to
rotate the guard by hand when the latch is closed.
Do not operate the grinder with a loose guard or
the guard latch in open position.
5. To remove the guard, open the guard latch, rotate
the guard so that the lugs and slots are aligned
and pull up on the guard.
ADJUSTING THE GUARD (FIGURE D)
Note: The guard is pre-adjusted to the diameter of
the gear case hub at the factory. If, after a period of
time, the guard becomes loose, tighten the adjusting screw
(10)withlatchintheclosedpositionandguardinstalledon
the tool.
CAUTION: Do not tighten the adjusting screw with the
latch in the open position. Undetectable damage to the guard
or the mounting hub may result.
CAUTION: If the guard cannot be tightened by the guard
latch, do not use the tool and take the tool and guard to a
service center to repair or replace the guard.
Note: Edge grinding and cutting can be performed with Type
27wheelsdesignedandspecifiedforthispurpose;1/4inch(6mm)thickwheelsare
designedforsurfacegrindingwhile1/8inch(3mm)wheelsaredesignedforedge
grinding. Cutting can also be performed by using a Type 1 wheel and a Type 1 guard.
OPERATION
SWITCHES
CAUTION: Hold the auxiliary handle and body of the tool firmly to maintain control
of the tool at start up and during use and until the wheel or accessory stops rotating.
Makesurethewheelhascometoacompletestopbeforelayingthetooldown.
NOTE: To reduce unexpected tool movement, do not switch the tool on or off while
under load conditions. Allow the grinder to run up to full speed before touching the work
surface. Lift the tool from the surface before turning the tool off. Allow the tool to stop
rotating before putting it down.
PADDLE SWITCH (FIGURE E)
Toturnthetoolon,pushthelock-offlever(1a)toward
the back of the tool, then depress the paddle switch
(1).Thetoolwillrunwhiletheswitchisdepressed.
Turn the tool off by releasing the paddle switch.
C
7
10
D
E
1
1a

9
4-1/2 inch (114mm) Grinding Wheels
Type27hubbedwheel
Type27guard
Type27guard
unthreaded
backing flange
threaded clamp nut
Type27depressed
center wheel
rubber backing pad
sanding disc
threaded clamp nut
Sanding Discs
Wire Wheels
3inchwire
cup brush
Type27guard
Type27guard
4inchwire
cup brush
4-1/2 inch (114mm)
Sanding Flap Discs
hubbed sanding
flap disc
unthreaded backing
flange
non-hubbed sanding
flap disc
threaded clamp nut
Type27guard
Type27guard
4-1/2 inch (114mm) Cutting Wheels
Type 1 guard
backing flange
abrasive cutting wheel
clamp nut
Type 1 guard
backing flange
diamond cutting wheel
clamp nut

10
SPINDLE LOCK
WARNING: To prevent accidental operation,
turn off and unplug tool before performing the
following operations. Failure to do this could result
in serious personal injury.
Thespindlelockbutton(6)isprovidedtoprevent
the spindle from rotating when installing or removing
wheels. Operate the spindle lock only when the tool is
turned off and the wheel has come to a complete stop.
WARNING: Do not engage the spindle lock while the tool is operating. Damage
to the tool will result and attached accessory may spin off possibly resulting in injury.
To engage the lock,depressthespindlelockbutton(6)showninfigure E1 and rotate
the spindle until you are unable to rotate the spindle further.
MOUNTING AND USING DEPRESSED CENTER GRINDING WHEELS AND
SANDING FLAP DISCS
MOUNTING AND REMOVING HUBBED WHEELS
WARNING: To prevent accidental operation, turn off and unplug tool before
performing the following operations. Failure to do this could result in serious
personal injury.
Hubbed wheels install directly on the 5/8 in.-11 threaded spindle.
1. Thread the wheel on the spindle by hand.
 2.Depressthespindlelockbuttonanduseawrench(figure E1)totightenthehubofthe
wheel.
 3.Reversetheaboveproceduretoremovethewheel.
CAUTION: Failure to properly seat the wheel before turning the tool on may result
in damage to the tool or the wheel.
MOUNTING NON-HUBBED WHEELS
WARNING: To prevent accidental operation, turn off and unplug tool before
performing the following operations. Failure to do
this could result in serious personal injury.
DepressedcenterType27grindingwheelsmustbe
usedwithincludedflanges.Seepages9and10ofthis
manual for more information.
1. Figure F - Install the unthreaded backing flange
(11)onspindle(12)withtheraisedsection(pilot)
against the wheel.
 2.Placewheelagainstthebackingflange,centering
thewheelontheraisedsection(pilot)ofthe
backing flange.
 3.Figure G - While depressing the spindle lock
button,threadthethreadedclampnut(13)on
spindle.
•Figure H - If the wheel you are installing is more
F
11
12
E1
6
G
13

11
than 1/8 inch (3mm) thick, place the threaded clamp nut on
the spindlesothattheraisedsection(pilot)fits into the center
of the wheel.
•Figure I - If the wheel you are installing is 1/8 inch (3mm) thick or less, place the
threaded clamp nut on the spindle so that the raised section
(pilot)is not against the wheel.
 4.Whiledepressingthespindlelockbutton(6),tightenthe
threaded clamp nut with included wrench.
5. To remove the wheel, depress the spindle lock button and
loosen the threaded clamp nut with included wrench.
NOTE: If the wheel spins after the threaded clamp nut is
tightened, check the orientation of the threaded clamp nut. If a
thin wheel is installed with the pilot on the clamp nut against the wheel, it will spin because
the height of the pilot prevents the clamp nut from holding the wheel.
SURFACE GRINDING WITH GRINDING WHEELS
1. Allow the tool to reach full speed before touching the tool to the
work surface.
 2.Applyminimumpressuretotheworksurface,allowingthetool
to operate at high speed. Grinding rate is greatest when the tool
operates at high speed.
 3.Figure J -Maintaina20˚to30˚anglebetweenthetoolandwork
surface.
 4.Continuouslymovethetoolinaforwardandbackmotiontoavoidcreatinggougesin
the work surface.
5. Remove the tool from work surface before turning tool off. Allow the tool to stop
rotating before laying it down.
EDGE GRINDING WITH GRINDING WHEELS
CAUTION: Wheels used for edge grinding may break or kick back if they bend or
twist while the tool is being used to do cut-off work. To reduce the risk of serious injury,
limittheuseofthesewheelswithastandardType27guardtoshallowcuttingand
notching(lessthan1/2inch(13mm)indepth).Theopensideoftheguardmustbe
positioned away from the operator. For deeper cutting with a Type 1 cut-off wheel, use a
closedType1guard.Seepage9formoreinformation.
1. Allow the tool to reach full speed before touching the tool to the work surface.
 2.Applyminimumpressuretotheworksurface,allowingthetooltooperateathigh
speed. Grinding rate is greatest when the tool operates at high speed.
 3.Positionyourselfsothattheopen-undersideofthewheelisfacingawayfromyou.
 4.Onceacutisbegunandanotchisestablishedintheworkpiece,donotchangethe
angle of the cut. Changing the angle will cause the wheel to bend and may cause
wheel breakage. Edge grinding wheels are not designed to withstand side pressures
caused by bending.
5. Remove the tool from the work surface before turning the tool off. Allow the tool to
stop rotating before laying it down.
CAUTION: Do not use edge grinding wheels / cutting wheels for surface grinding
applications because these wheels are not designed for side pressures encountered with
surface grinding. Wheel breakage and injury may result.
1/8 inch WHEELS
Backing Flange
Threaded Clamp Nut
I
1/4inch WHEELS
Backing Flange
Threaded Clamp Nut
H
J
20˚-30˚

SURFACE FINISHING WITH SANDING FLAP DISCS
1. Allow the tool to reach full speed before touching the tool to the work surface.
 2.Applyminimumpressuretoworksurface,allowingthetooltooperateathighspeed.
Sanding rate is greatest when the tool operates at high speed.
 3.Figure K - Maintaina5˚to10˚anglebetweenthetoolandwork
surface.
 4.Continuouslymovethetoolinaforwardandbackmotiontoavoid
creating gouges in the work surface.
5. Remove the tool from work surface before turning tool off. Allow
the tool to stop rotating before laying it down.
MOUNTING SANDING BACKING PADS
WARNING: To prevent accidental operation, turn off and unplug tool before
performing the following operations. Failure to do this could result in serious
personal injury.
NOTE: Guard may be removed when using sanding backing pads.
WARNING: Proper guard must be reinstalled for grinding wheel, sanding flap disc,
cutting wheel, wire brush or wire wheel applications after sanding
applications are complete.
1. Figure L - Placeorappropriatelythreadbackingpad(14)
on the spindle.
 2.Placethesandingdisc(15)onthebackingpad(14).
 3.Whiledepressingspindlelock,threadclampnut(13)on
spindle, piloting the raised hub on the clamp nut into the
center of sanding disc and backing pad.
 4.Tightentheclampnutbyhand,thendepressthespindle
lock button while turning the sanding disc until the sanding
disc and clamp nut are snug.
5. To remove the wheel, grasp and turn the backing pad and
sanding pad while depressing the spindle lock button.
USING SANDING BACKING PADS
Choose the proper grit sanding discs for your application. Sanding discs are available in
various grits. Coarse grits yield faster material removal rates and a rougher finish. Finer
grits yield slower material removal and a smoother finish.
Beginwithcoarsegritdiscsforfast,roughmaterialremoval.Movetoamediumgrit
paper and finish with a fine grit disc for optimal finish.
Coarse 16-30grit
Medium 36-80grit
FineFinishing 100-120grit
Very Fine Finishing 150 - 180 grit
1. Allow the tool to reach full speed before touching tool to the work surface.
 2.Applyminimumpressuretoworksurface,allowingthetooltooperateathighspeed.
Sanding rate is greatest when the tool operates at high speed.
 3. Figure M - Maintaina5˚to15˚anglebetweenthetoolandwork
surface. The sanding disc should contact approximately one inch
(25mm)ofworksurface.
 4.Movethetoolconstantlyinastraightlinetopreventburningand
swirling of work surface. Allowing the tool to rest on the work
surface without moving, or moving the tool in a circular motion
causes burning and swirling marks on the work surface.
5. Remove the tool from work surface before turning tool off. Allow the tool to stop
rotating before laying it down.
PRECAUTIONS TO TAKE WHEN SANDING PAINT
 1.SandingofleadbasedpaintisNOTRECOMMENDEDduetothedifficultyof
controlling the contaminated dust. The greatest danger of lead poisoning is to children
and pregnant women.
 2.Sinceitisdifficulttoidentifywhetherornotapaintcontainsleadwithoutachemical
analysis, we recommend the following precautions when sanding any paint:
1212
K
5˚-10˚
13
14
15
L
M
5˚-15˚

PERSONAL SAFETY
1. No children or pregnant women should enter the work area where the paint sanding
is being done until all clean up is completed.
 2.Adustmaskorrespiratorshouldbewornbyallpersonsenteringtheworkarea.The
filter should be replaced daily or whenever the wearer has difficulty breathing.
NOTE: Only those dust masks suitable for working with lead paint dust and fumes
should be used. Ordinary painting masks do not offer this protection. See your local
hardware dealer for the proper N.I.O.S.H. approved mask.
 3.NOEATING,DRINKINGorSMOKINGshouldbedoneintheworkareatoprevent
ingesting contaminated paint particles. Workers should wash and clean up BEFORE
eating, drinking or smoking. Articles of food, drink, or smoking should not be left in the
work area where dust would settle on them.
ENVIRONMENTAL SAFETY
1. Paint should be removed in such a manner as to minimize the amount of dust
generated.
 2.Areaswherepaintremovalisoccurringshouldbesealedwithplasticsheetingof
4milsthickness.
 3.Sandingshouldbedoneinamannertoreducetrackingofpaintdustoutsidethework
area.
CLEANING AND DISPOSAL
1. All surfaces in the work area should be vacuumed and thoroughly cleaned daily for
the duration of the sanding project. Vacuum filter bags should be changed frequently.
 2.Plasticdropclothsshouldbegatheredupanddisposedofalongwithanydustchips
or other removal debris. They should be placed in sealed refuse receptacles and
disposed of through regular trash pick-up procedures.
During clean up, children and pregnant women should be kept away from the
immediate work area.
 3.Alltoys,washablefurnitureandutensilsusedbychildrenshouldbewashed
thoroughly before being used again.
MOUNTING AND USING WIRE BRUSHES AND WIRE WHEELS
Wire cup brushes or wire wheels screw directly on the grinder spindle without the use of
flanges. Use only wire brushes or wheels provided with a 5/8 inch-11 threaded hub. A
Type27guardisrequiredwhenusingwirebrushesandwheels.
CAUTION: Wear work gloves when handling wire brushes and wheels. They
can become sharp.
CAUTION: Wheel or brush must not touch guard when mounted or while in use.
Undetectable damage could occur to the accessory, causing wires to fragment from accessory
wheel or cup.
MOUNTING WIRE CUP BRUSHES AND WIRE WHEELS
WARNING: To prevent accidental operation, turn off and unplug tool before
performing the following operations. Failure to do this could result in serious
personal injury.
1. Thread the wheel on the spindle by hand.
 2.Depressspindlelockbuttonanduseawrenchonthehubofthewirewheelorbrush
to tighten the wheel.
 3.Toremovethewheel,reversetheaboveprocedure.
CAUTION: Failure to properly seat the wheel hub before turning the tool on may
result in damage to tool or wheel.
USING WIRE CUP BRUSHES AND WIRE WHEELS
Wire wheels and brushes can be used for removing rust, scale and paint, and for
smoothing irregular surfaces.
NOTE: The same precautions should be taken when wire brushing paint as when
sandingpaint(seepage13).
1. Allow the tool to reach full speed before touching the tool to the work surface.
 2.Applyminimumpressuretoworksurface,allowingthetooltooperateathighspeed.
1313

1414
Materialremovalrateisgreatestwhenthetooloperatesathighspeed.
 3.Figure N -Maintaina5˚to10˚anglebetweenthetoolandworksurfaceforwirecup
brushes.
 4.Maintaincontactbetweentheedgeofthewheelandthework
surface with wire wheels.
5. Continuously move the tool in a forward and back motion to avoid
creating gouges in the work surface. Allowing the tool to rest on
the work surface without moving, or moving the tool in a circular
motion causes burning and swirling marks on the work surface.
 6.Removethetoolfromtheworksurfacebeforeturningthetooloff.
Allow the tool to stop rotating before setting it down.
CAUTION: Use extra care when working over an edge, as a sudden sharp
movement of grinder may be experienced.
MOUNTING AND USING CUTTING (TYPE 1) WHEELS
Cutting wheels include diamond wheels and abrasive discs. Abrasive cutting wheels for
metal and concrete use are available. Diamond blades for concrete cutting can also be
used.
WARNING: Aclosed,2-sidedcuttingwheelguardisrequiredwhenusingcutting
wheels. Failure to use proper flange and guard can result in injury resulting from wheel
breakageandwheelcontact.Seepage9formoreinformation.
MOUNTING CLOSED (TYPE 1) GUARD
WARNING: To prevent accidental operation, turn off and unplug tool before
performing the following operations. Failure to do this could result in serious
personal injury.
1. Figure B-Opentheguardlatch(7),andalignthelugsontheguard(8)withtheslots
onthegearcasecover(9).
 2.Pushtheguarddownuntiltheguardlugsengageandrotatefreelyinthegrooveon
the gear case hub.
 3.Withtheguardlatchopen,rotatetheguardintothedesiredworkingposition.The
guard body should be positioned between the spindle and the operator to provide
maximum operator protection.
 4.Figure C-Closetheguardlatch(7)tosecuretheguardonthegearcase.You
should not be able to rotate the guard by hand when the latch is closed. Do not
operate the grinder with a loose guard or the guard latch in open position.
5. To remove the guard, open the guard latch, rotate the guard so that the lugs and slots
are aligned and pull up on the guard.
Note: The guard is pre-adjusted to the diameter of the gear case hub at the factory. If,
afteraperiodoftime,theguardbecomesloose,tightentheadjustingscrew(10)with
latch in the closed position and guard installed on the tool.
CAUTION: Do not tighten the adjusting screw with the latch in the open position.
Undetectable damage to the guard or the mounting hub may result.
MOUNTING CUTTING WHEELS
WARNING: To prevent accidental operation, turn off and unplug tool before
performing the following operations. Failure to do this could result in serious
personal injury.
CAUTION: Matchingdiameterbackingflangeandthreadedclampnut(included
withtool)mustbeusedforcuttingwheels.
 1.Placetheunthreadedbackingflangeonspindlewiththeraisedsection(pilot)facing
up.Theraisedsection(pilot)onthebackingflangewillbeagainstthewheelwhen
the wheel is installed.
 2.Placethewheelonthebackingflange,centeringthewheelontheraisedsection(pilot).
 3.Installthethreadedclampnutwiththeraisedsection(pilot)facingawayfromthewheel.
 4.Depressthespindlelockbuttonandtightenclampnutwithincludedwrench.
5. To remove the wheel, grasp and turn the wheel while depressing the spindle lock button.
N
5˚-10˚

1515
USING CUTTING WHEELS
WARNING: Do not use edge grinding/cutting wheels for surface grinding
applications because these wheels are not designed for side pressures encountered with
surface grinding. Wheel breakage and injury may result.
1. Allow tool to reach full speed before touching tool to work surface.
 2.Applyminimumpressuretoworksurface,allowingtooltooperateathighspeed.
Cutting rate is greatest when the tool operates at high speed.
 3.Onceacutisbegunandanotchisestablishedintheworkpiece,donotchangethe
angle of the cut. Changing the angle will cause the wheel to bend and may cause
wheel breakage.
 4.Removethetoolfromworksurfacebeforeturningtooloff.Allowthetooltostop
rotating before setting it down.
Maintenance
CLEANING
WARNING: Blowing dust and grit out of the motor housing using compressed air
is a necessary maintenance procedure. Dust and grit from metal grinding often
accumulate on interior surfaces and could create an electrical shock hazard if not
cleaned out.
WARNING: ALWAYS use safety glasses. Everyday eyeglasses are NOT safety
glasses. Also use face or dust mask if operation is dusty. ALWAYS WEAR CERTIFIED
SAFETY EQUIPMENT:
  •ANSIZ87.1eyeprotection(CAN/CSAZ94.3),
  •ANSIS12.6(S3.19)hearingprotection,
  •NIOSH/OSHA/MSHArespiratoryprotection.
Use only mild soap and a damp cloth to clean the tool. Never let any liquid get inside the
tool;neverimmerseanypartofthetoolintoaliquid.
IMPORTANT: To assure product SAFETY and RELIABILITY, repairs, maintenance and
adjustment(otherthanthoselistedinthismanual)shouldbeperformedbyauthorized
service centers or other qualified service personnel, always using identical replacement parts.
LUBRICATION
Bostitch tools are properly lubricated at the factory and are ready for use. Tools should
belubricatedregularlyeveryyeardependingonusage.(Toolsusedonheavydutyjobs
andtoolsexposedtoheatmayrequiremorefrequentlubrication.)Thislubricationshould
be attempted only by trained power tool repair person such as those at Bostitch service
centers or in other qualified service personnel.
REPLACEMENT PARTS
Use only identical replacement parts. For a parts list or to order parts, visit our service
website at www.bostitch.com. You can also order parts from your nearest Bostitch
Factory Service Center or Bostitch Authorized Warranty Service Center. Or, you can call
ourCustomerCareCenterat(800)2622161.
SERVICE AND REPAIRS
All quality tools will eventually require servicing and/or replacement of parts. For
information about Bostitch, its factory service centers or authorized warranty service
centers, visit our website at www.bostitch.com or call our Customer Care Center at
(800)2622161.Allrepairsmadebyourservicecentersarefullyguaranteedagainst
defective material and workmanship. We cannot guarantee repairs made or attempted
by others.
You can also write to us for information at Bostitch, 701 E. Joppa Road, Towson,
Maryland21286-Attention:ProductService.Besuretoincludealloftheinformation
shownonthenameplateofyourtool(modelnumber,type,serialnumber,etc.).

16
ACCESSORIES
WARNING: Since accessories, other than those offered by Bostitch have not
been tested with this product, use of such accessories with this tool could be hazardous.
To reduce the risk of injury, only Bostitch recommended accessories should be used
with this product.
A complete line of accessories is available from your Bostitch Factory Service Center or
a Bostitch Authorized Warranty Service Center. Please visit our Web Site
www.bostitch.com for a catalog or for the name of your nearest supplier.
THREE YEAR LIMITED WARRANTY
Bostitch will repair or replace, without charge, any defects due to faulty materials or
workmanshipforthreeyearsfromthedateofpurchasefortools(twoyearsforbatteries).
This warranty does not cover part failure due to normal wear or tool abuse. For further detail
of warranty coverage and warranty repair information, visit www.
bostitch .com or call (800)
262-2161. This warranty does not apply to accessories or damage caused where repairs
have been made or attempted by others. This warranty gives you specific legal rights and
you may have other rights which vary in certain states or provinces.
In addition to the warranty, Bostitch tools are covered by our: 1 YEAR FREE SERVICE:
Bostitch will maintain the tool and replace worn parts caused by normal use, for free,
any time during the first year after purchase.
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TROUBLESHOOTING
Problem Possible Cause Possible Solution
• Unitwillnotstart. •Cordnotpluggedin. •Plugtoolintoaworkingoutlet.
  •Circuitfuseisblown. •Replacecircuitfuse.(Ifthe
product repeatedly causes the
circuit fuse to blow, discontinue
use immediately and have it
serviced at a Bostitch
service center or authorized
   servicer.)  
 •Circuitbreakeristripped. •Resetcircuitbreaker.(Ifthe
product repeatedly causes the
circuit breaker to trip,
discontinue use immediately
and have it serviced at a
Bostitch service center or
   authorizedservicer.) 
 •Cordorswitchisdamaged. •Havecordorswitchreplaced
at a Bostitch Service
Center or Authorized Servicer
For assistance with your product, visit our website at www.bostitch.com for a list of service
centers, or call the Bostitch Customer Care Center at
[phone] .
ThisClassBdigitalapparatuscomplieswithCanadianICES-003.Thisdevicecomplies
withpart15oftheFCCrules.Operationissubjecttothefollowingtwoconditions:(1)
Thisdevicemaynotcauseharmfulinterference,and(2)thisdevicemustacceptany
interference received, including interference that may cause undesired operation.
NOTE: This equipment has been tested and found to comply with the limits for Class B
digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide
reasonable protection against harmful interference in a residential installation. This
equipment generates, uses and can radiate radio frequency energy and, if not installed
and used in accordance with the instructions, may cause harmful interference to radio or
television reception, which can be determined by turning the equipment off and on, the user
is encouraged to try to correct the interference by one or more of the following measures:
 •Reorientorrelocatethereceivingantenna.
 •Increasetheseparationbetweentheequipmentandthereceiver.
 •Connecttheequipmentintoanoutletonacircuitdifferentfromthattowhichthereceiveris
connected.
 •Consultthedealeroranexperiencedradio/TVtechnicianforhelp.

1717
90 DAY MONEY BACK GUARANTEE: If you are not completely satisfied with the
performanceofyourBostitchPowerToolforanyreason,youcanreturnitwithin90days
from the date of purchase with a receipt for a full refund – no questions asked.
LATIN AMERICA: This warranty does not apply to products sold in Latin America. For
products sold in Latin America, see country specific warranty information contained in
the packaging, call the local company or see website for warranty information.
To register your tool for warranty service visit our website at www.bostitch.com
WARNING LABEL REPLACEMENT
Ifyourwarninglabelsbecomeillegibleoraremissing,call(800)262-2161forafreereplacement.
Imported by Bostitch
701 E. Joppa Road
Towson,Maryland21286